sunoftzu, an effective defense for the Americans in S4 is from the 10-2/667/HMG and 8-1/666/MMG to run back to into P1, run a 747/FT in to Z1, a 666/ MMG in V6, 8-0 and 3 546s run back into I2, 747/FT in H3. Of course the American setup does not allow initial placement in all these hexes but they are good positions to keep the horde at bay. I have seen this or similar defenses with kill stack in P1 and V6/V3, FTs on the wings work repeatedly. Of course if the dice gods are against the Americans, there is little that can be done. I tutor newbies in SK and this is the defense I suggest. I have never seen it broken by me or another player when even average rolls are made by the Americans. Let me know what you think by pm.